1. Field of the Invention
This invention relates to prophylactics for the ear that keep harmful foreign objects from contacting the ear canal and ear drum of a user when he or she is positioned at or below the surface of fresh water, saltwater, or any other liquid medium that is likely transport unwanted foreign matter into an ear. The present invention, which may be reusable, provides protection of a user's ear from barotraumas and infection when the user is subjected to pressures ranging from one to approximately twelve atmospheres. This makes the present invention ideal for use by those engaging in surface and subsurface marine construction and maintenance, as well as use by sport divers. Unless the diaphragm is protected by an optional external barrier, it is not contemplated for the present invention to be used in activities where a sudden impact might occur to the ear, such as but not limited to water skiing, use of personal watercraft, snow skiing, use of snow mobiles, and surfing.
2. Description of the Related Art
Commercial divers, pile drivers, hull scrapers, and others often work in shallow water without any type of ear protection against water or fluid carried infection-causing contaminants, even though their work environment repeatedly places their ear drums and ear canals at risk for exposure to unhealthy substances, such as mud, barnacles, oil, hydraulic fluid, creosote, organic materials, plant and animal life, bacteria, and other debris. Sport divers also place themselves at risk for ear disorders every time they dive and snorkel without ear protection in water that contains infection causing debris and bacteria, an occurrence that appears to be of increasing concern in recreational waters. Although many types of ear plugs exist, until use of the present invention, none appear to completely block the passage between the outer ear and the ear drum while concurrently allowing the equalization of pressure through the use of an elastic diaphragm positioned across one end of an inner sleeve. Preferably, the diaphragm end of the inner sleeve is positioned remote from the outer ear, however, when using the present invention where pressures would not exceed approximately two atmospheres, it is considered to be within the scope of the present invention for the diaphragm end of the sleeve to be in a reversed position remote from the ear canal. When the elastic diaphragm is positioned closer to the ear canal, the displacement needed to equalize pressure is less than when the present invention diaphragm is positioned remotely from the ear canal. Optionally, an additional seal can be used between the present invention body and sleeve to help the body fit more snugly within the user's outer ear, such as but not limited to a non-drying permanently tacky glue. No ear prophylactic is known that has the same structure or all of the advantages offered by the present invention.
The invention is thought to be most closely associated with the present invention is U.S. Pat. No. 5,488,961 to Adams (1996). However, there are important differences between the Adams invention and the present invention. Adams discloses a hollow elongated earplug with a uniformly tapering outer surface and a lumen along the ear canal. A hydrophobic membrane extends across the lumen to selectively block water entry into the ear canal while admitting air movement into and out of the ear canal to equalize air pressure and improve the user's hearing. The Adams membrane extends laterally into the interior walls of the plug body. Optionally, for ear protection when greater fluid pressures are involved, the Adams membrane can have a support structure, which is shown and described to be two concentric circles joined by four radial extensions. The support structure is always on the side of the membrane adjacent to the distal end of the plug body. When such a support structure is used, it also extends laterally into the interior walls of the plug body. A third optional Adams structure is disclosed, which allows for substitution of membranes having different pore diameters, water break through ratings, and/or air flow rates for use at different fluid depths. The Adams membrane and its support structure are then secured laterally within the interior surface of a mounting assembly that is removable from the plug body. Although the Adams mounting assembly is generally cylindrical, it has a step-down configuration that gives its distal portion 36B a smaller diameter than its proximal portion 36A. Thus, when the Adams plug body is removed from an ear, a new mounting assembly with a different membrane can be inserted into the plug body in place of the previously used mounting assembly/membrane combination. The present invention can be distinguished from the Adams invention in several important ways. First, the present invention diaphragm is different from the Adams membrane. While the Adams membrane selectively allows air to pass through it, but not water and debris, the present invention stretchable diaphragm completely blocks entry of everything from getting into the ear canal, including air. Thus, the Adams membrane equalizes pressure by letting air pass through it, while the present invention stretchable diaphragm equalizes pressure by physical displacement. Also, the present invention device is simpler in construction and discloses a different exterior plug configuration than the Adams invention. While the exterior configuration of the Adams invention is uniformly tapering, the corresponding feature of the present invention has a two-stage tapering configuration with the difference in the diameter of wide end to narrow end being greater for the outer ear section instead of the opposing ear canal section. Further, the membrane of the present invention is sealed across one end of a non-collapsing, flexible, and hollow cylindrical sleeve, while the membrane of the Adams invention extends laterally into the walls of the plug body or a mounting assembly positioned within the plug body. When the Adams invention uses a mounting assembly, its plug body must have an interior surface with a step-down configuration at one end to accommodate the complementary exterior step-down configuration on the exterior surface of the Adams mounting assembly. The step-down configuration would prevent reverse end-to-end orientation of the Adams mounting assembly, whereby the sleeve of the present invention has no step-down exterior configuration so that its end-to-end orientation can be reversed when preferred for use in fluids with differing pressures. The need for the Adams membrane support structure to always remain adjacent to the distal end of the plug body would also prevent the end-to-end reversal of the Adams mounting assembly. Also, the Adams invention teaches replacement of its mounting assembly with another having a new membrane configured for use at a different fluid depth, while the present invention discloses reversing the end-to-end orientation of its sleeve for fluid pressure adaptation by a single membrane between one and approximately twelve atmospheres. Thus, the Adams invention does not teach all of the structure and advantages provided by the present invention.
Other earplug inventions having pressure equalizing membranes or partitions are U.S. Pat. No. 5,881,729 to Castillo (1999) and U.S. Pat. No. 2,437,490 to Watson (1948). Watson discloses a hollow and elongated pressure-regulating earplug that equalizes pressure in the user's ear canal and also provides sound insulation. The Watson invention has a flared outer portion, an opposing orifice, and a reduced inner portion between the outer portion and the orifice with the inner portion having spaced flanges on its exterior surface and a substantially cylindrical configuration. Watson further has one or two partitions between the flared outer portion and the orifice, with each partition having an air pressure equalizing unit that is acoustically packed with cotton or other packing material that muffles sound yet permits the rapid equalization of air pressure in the ear canal through the plug. The Watson invention does not teach a removable rigid inner sleeve with a stretchable diaphragm on one of its ends that equalizes pressure by physical displacement. In contrast, Castillo discloses a hollow elongated water sports earplug that has a membrane to prevent wind and water from entering a user's ear while permitting sound to pass through the membrane. The exterior configuration of the Castillo invention plug body is similar to that of the Watson invention, with a flared outer portion, an opposing orifice, and a reduced inner portion between the outer portion and the orifice, with the inner portion having a substantially cylindrical configuration. However, instead of partitions with air pressure equalizing units that are acoustically packed with sound blocking material, the Castillo invention has an insert that fits into its cylindrical inner portion. The insert has an annular retaining member, a membrane, and a generally annular insert housing for the membrane which positions the membrane axially close the second end of the insert housing. Thus, when the insert is located within the plug body, it does not extend the full length of the plug body, leaving the membrane positioned between the flared outer portion and the reduced inner portion of the Castillo invention. In contrast, the non-collapsing, flexible present invention inner sleeve extends the full length of its respective plug body. Also, its diaphragm is preferably positioned at the orifice end of its respective plug body, although it is also possible to position the present invention diaphragm remote from the ear canal. However, in either of its two possible positions, since the inner sleeve of the present invention is substantially similar in length to its respective plug body and its stretchable diaphragm is positioned across one of the opposing ends of the sleeve, the diaphragm of the present invention does not have a centered positioning within its plug body, as is taught by the Castillo invention.